IPA: /ˈfɛstəvli/
KK: /ˈfɛstəvli/
In a way that is cheerful and celebratory, often associated with festivals or special occasions.
The children decorated the hall festively for the holiday party.
Festively → It is formed from "festive" (from Latin *festivus*, meaning of a feast or festival) and the suffix "-ly" (meaning in a manner of). The word "festively" means in a manner that is cheerful and celebratory, like a feast or festival.
Think of the word 'festive' which relates to celebrations and feasts, and remember that 'festively' means doing something in a cheerful, celebratory way.